Typical Installation

Retrofit Installation

Testing the Unit

Backwater Valve Specifications

Access Box Specifications


Retrofit Installation Of Backwater Valve

  • Failures may occur due to back grade on valves. In order to achieve grade in retrofit installations, an installer must expose approx. 4-5 feet of piping. Often sewers are at a minimum, flat, or back grading. Since there is 3/4 of an inch difference in height from inlet to outlet on your Mainline valve, it may be necessary to adjust the grade on the piping leading up to the valve, to achieve required grade on the backwater valve
  • In retrofit installations, always run and test all fixtures to ensure each one runs through the backwater valve, and nothing remains unprotected
  • Check that the sewer is unrestricted (roots, blockages, etc.) downstream of valve.
  • Ensure weeping tiles (French drains) tie in downstream of valve

  • Improper installation may result in valve failure
  • Follow installation procedures carefully, with special care and attention to be taken when retrofitting valve into existing systems
  • Do not install if proper grade cannot be achieved
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